A last-ditch effort by Angela Merkel and François Hollande to prevent the Ukraine conflict escalating brought an agreement to restart four-way peace talks with Russia's Vladimir Putin and Ukraine's Petro Poroshenko.
But it was unclear if anything more concrete had been achieved, and the two western leaders left Moscow late on Friday without talking publicly.
The German and French leaders flew to the Russian capital a day after lengthy talks with Mr Poroshenko, the Ukrainian president, in Kiev as concern grew in Europe over a flare-up in the war in the east of his country and an increasingly muscular debate in the US about the possibility of supplying Ukraine with weapons.
After more than five hours of talks, described by Moscow as "constructive", the Kremlin said work was under way to draft a joint document on how a ceasefire deal drawn up in Minsk in September, which has since broken down, could be implemented.
The three leaders and Ukraine's president would continue talks on the phone on Sunday, Mr Putin's spokesman Dmitry Peskov said.
The document "would include the Ukrainian president's proposals and proposals formulated and added today by [Mr] Putin", Mr Peskov said.